Astrofísica Estelar


Preocupa-se em estudar as estrelas sua evolução, fundamentais para o entendimento do Universo. A astrofísica estelar pode ser estudada através de observação, entendimento teórico e por simulações em computador. Especificamente na parte observacional, o único dado possível de se coletar dos astros é a radiação que eles emitem, desta maneira, utilizando de técnicas avançadas conseguimos determinar massas, temperaturas, composições químicas, idades, características cinemáticas e várias outros parâmetros físicos das estrelas.



- Prof. Dr. Rafael Miloni Santucci

Projeto de pesquisa: Understanding the Stellar Halo of the Milky Way Galaxy

Descrição: The main goal of this project is to gather all relevant information about the halo system of the Milky Way galaxy and, from the analysis of large databases available in the literature and observation of pre-selected objects, contribute to the understanding of this very peculiar structural component of the Galaxy. Systematic surveys of the Galaxy, such as the Sloan Digital Sky Survey (SDSS), increased by orders of magnitude the amount of stellar data collected in recent decades, and have drastically changed our view of the structure of the Galaxy, revealing components that until then remained obscure due to the lack of appropriate statistics. This proposal builds upon on the work started out by my research group in Galactic Archaeology, which has achieved important results in the process of search, analysis, and understanding of metal-poor stars of various sub-classes: carbon-enhanced metal-poor (CEMP) stars, blue stragglers stars (BSS) and blue horizontal branch (BHB) stars. Medium and high-resolution spectroscopy will be part of observations in 4-meter and 8-meter class telescopes (such as SOAR, Gemini, etc.), in which Brazil has active participation. These observations will allow for the determination of precise abundances of other heavier chemical elements, produced by neutron-capture processes, vital for the understanding of the chemical evolution of single and binary stars, of the Milky Way itself and consequently of the early Universe. These heavy elements are thought to be the byproduct of the kilonova explosion following a neutron-star merger, according to recent observations by LIGO (Laser Interferometer Gravitational-Wave Observatory). In addition, the analysis of the kinematic properties of these objects, through the data collected from the GAIA satellite, will allow us to explore in more detail the correlations between chemical abundance patterns and their possible formation sites within the complex structure of the Milky Way.